Headache spectrum in Arnold-Chiari malformation.

Exertional headaches in patients with Arnold-Chiari malformation (ACM) are well described. We report four patients with Type I ACM and recurrent headaches. These patients presented, respectively, with low spinal fluid pressure headache, migraine without aura, migraine with aura, and migraine with prolonged aura. This report suggests the need for observing patients with recurrent headaches for any physical stigmata of craniovertebral junction anomalies, and the need to exclude ACM in such patients. Possible implications of the association between ACM and different types of headaches are discussed.